Field of the Disclosure
The present invention relates to an organic light emitting display device, and more particularly, to a top emission type organic light emitting display device.
Discussion of the Related Art
An organic light emitting display (OLED) device, which is a self light emitting display device, has advantages of low power consumption, rapid response speed, high emission efficiency, high luminance, and wide viewing angle. According to a direction of light emitted from an organic light emitting device, the OLED device may generally be classified into a top emission type and a bottom emission type. In a bottom emission type, a circuit device is disposed between a light emitting layer and an image displaying surface, thereby reducing an aperture ratio due to the circuit device. Meanwhile, in a top emission type, a circuit device is not disposed between a light emitting layer and an image displaying surface, thereby improving an aperture ratio.
FIG. 1 is a cross sectional view of a related art top emission type OLED device.
As shown in FIG. 1, a thin film transistor layer (T) including an active layer 11, a gate insulating film 12, a gate electrode 13, an insulating interlayer 14, a source electrode 15, and a drain electrode 16 is provided on a substrate 10. Then, a passivation layer 20 and a planarization layer 30 are sequentially provided on the thin film transistor layer (T).
Also, an anode electrode 40 and an auxiliary electrode 50 are provided on the planarization layer 30. The auxiliary electrode 50 is provided to lower a resistance of a cathode electrode 80, as will be explained later. On the anode electrode 40 and the auxiliary electrode 50, a bank 60 is provided to define a pixel region. Also, an organic emitting layer 70 is provided in the pixel region defined by the bank 60, and the cathode electrode 80 is provided on the organic emitting layer 70.
In the top emission type, light emitted from the organic emitting layer 70 passes through the cathode electrode 80. For this reason, the cathode electrode 80 is formed of a transparent conductive material, which causes an increase of resistance therein. To lower the resistance of the cathode electrode 80, the cathode electrode 80 is connected with the auxiliary electrode 50.
In the top emission type OLED device according to the related art, there is a difficulty in depositing the organic emitting layer 70. If the organic emitting layer 70 is deposited only on the anode electrode 40 in the OLED device according to the related art, an additional process is needed. But, if the organic emitting layer 70 is deposited on an entire surface of the OLED device, it is impossible to connect the auxiliary electrode 50 and the cathode electrode 80 with each other.